Spinal Correction Research Articles

Complications Associated With Oblique Lumbar Interbody Fusion at L5-S1: A Systematic Review of the Literature

Abstract INTRODUCTION Oblique lumbar interbody fusion (OLIF) at L5-S1, also known as a lateral decubitus anterior lumbar interbody fusion (ALIF) or anterior-to-psoas (ATP) approach, is a technique that provides a minimally invasive corridor to a key segment in the spine for degenerative conditions and deformity correction. However, the evaluation of complications associated with this level has been difficult as prior reports include other levels that have different anatomic considerations. OBJECTIVE To present a systematic review of previously reported cases of OLIF, lateral ALIF, and an ATP approach at L5-S1 to discuss their associated complications. METHODS Following preferred reporting items for systematic reviews and meta-analyses (PRISMA) guidelines, a PubMed search was performed up to January 2021 to identify literature describing OLIF, lateral ALIF, and ATP approaches involving the L5-S1 levels. A quality assessment with risk of bias analysis was performed using the methodological index for non-randomized studies (MINORS) assessment tool for each study. Data we then extracted to identify all complications. RESULTS The initial search yielded 532 publications. After screening, there were 18 studies with 553 total patients who underwent OLIF including L5-S1. Analysis of these studies demonstrated a vascular complication rate of 2.5%, bowel-associated complication rate of 0.5%, ureteral injury rate of 0%, neurological injury rate of 1.9%, pseudarthrosis rate of 7.3%, and reoperation rate of 2.2%. CONCLUSION The L5-S1 level remains an important target for sagittal alignment in both degenerative and deformity surgery. The OLIF surgical corridor to this level presents special anatomic and clinical considerations and is a safe approach to minimize morbidity with minimally invasive access.

Differential diagnosis of a calcified cyst found in an 18th century female burial site at St. Nicholas Church cemetery (Libkovice, Czechia).

During archaeological excavations in burial sites, sometimes stoned organic objects are found, in addition to human remains. Those objects might be of a different origin, depending on various factors influencing members of a community (i.e. diseases, trauma), which provides information about their living conditions. The St. Nicholas Church archaeological site (Libkovice, Czechia) in the 18th century horizon of the cemetery, yielded a maturus-senilis female skeleton with a stone object in the left iliac fossa. This object was an oviform cyst-like rough structure, measuring 54 mm in length, 35 mm in maximum diameter and 0.2-0.7 mm shell thickness. Within the object there were small fetal bones (long bones, i.e. femur and two tibias, two scapulas, three ribs, vertebrae and other tiny bone fragments). Methods utilized to analyze the outer and inner surface morphology of the cyst and its inside, included: X-ray, CT imaging, SEM, histological staining and EDS. The EDS analysis revealed the presence of primarily oxygen, calcium and phosphorus in bone samples, and oxygen and silicon, in stone shell. Based on the length of the femur (20.2 mm) and tibia (16 mm) shafts, the fetal age was determined as being in the 15-18 week of pregnancy. The differential diagnosis was conducted, including for the three most probable cases: fetiform teratoma (FT), fetus-in-fetu (FIF) and lithopedion. The possibility of fetiform teratoma was discounted due to the presence of an anatomically correct spine, long bones and the proportions of the find. Although the low calcium content in the shell (2.3% atom mass), the lack of skull bones and the better developed lower limbs indicate fetus-in-fetu rather than lithopedion, the analyses results are unable to conclusively identify the object under one of these two categories since there are insufficient such cases in excavation material with which to draw comparison.

In vivo deformation of anatomically pre-bent rods in thoracic adolescent idiopathic scoliosis

Some surgical strategies can maintain or restore thoracic kyphosis (TK); however, next-generation surgical schemes for adolescent idiopathic scoliosis (AIS) should consider anatomical corrections. A four-dimensional correction could be actively achieved by curving the rod. Thus, anatomically designed rods have been developed as notch-free, pre-bent rods for easier anatomical reconstruction. This study aimed to compare the initial curve corrections obtained using notch-free rods and manually bent, notched rods for the anatomical reconstruction of thoracic AIS. Two consecutive series of 60 patients who underwent anatomical posterior correction for main thoracic AIS curves were prospectively followed up. After multilevel facetectomy, except for the lowest instrumented segment, either notch-free or notched rods were used. Patient demographic data, radiographic measurements, and sagittal rod angles were analyzed within 1 week after surgery. Patients with notch-free rods had significantly higher postoperative TK than patients with notched rods (P < .001), but both groups achieved three-dimensional spinal corrections and significantly increased postoperative rates of patients with T6–T8 TK apex (P = .006 for notch-free rods and P = .008 for notched rods). The rod deformation angle at the concave side was significantly lower in the notch-free rods than in the notched rods (P < .001). The notch-free, pre-bent rod can maintain its curvature, leading to better correction or maintenance of TK after anatomical spinal correction surgery than the conventional notched rod. These results suggest the potential benefits of anatomically designed notch-free, pre-bent rods over conventional, manually bent rods.

Cobalt-chromium versus titanium alloy rods for correction of adolescent idiopathic scoliosis based on 1-year follow-up: a multicenter randomized controlled clinical trial.

For instrumented correction surgery for adolescent idiopathic scoliosis (AIS), surgeons are increasingly switching from titanium (Ti) alloy rods to stiffer cobalt-chromium (CoCr) rods. The authors conducted the first multicenter randomized controlled clinical trial to investigate whether these materials affect the outcomes in terms of spine correction and quality of life (QOL). This trial was registered at UMIN Clinical Trials Registry on September 3, 2012, under the identifier UMIN000008838 (level of evidence 1). Female AIS patients (Lenke types 1-3, patient age 10-19 years) were recruited at 5 Japanese institutions and randomized into two cohorts: 6.0-mm-diameter Ti rods were placed in one group, and 6.0-mm-diameter CoCr rods were placed in the other. Patients were followed up at 2 weeks and 3, 6, and 12 months with radiographic examination to quantify the sagittal and coronal correction (Cobb angle, thoracic kyphosis, rib hump, and apical vertebral rotation). Patients completed questionnaires (Scoliosis Research Society-22r, 12-Item Short-Form Health Survey, and Scoliosis Japanese Questionnaire-27) at 6 and 12 months to assess QOL. A total of 69 AIS patients were randomized to the demographically similar Ti (n = 37) or CoCr (n = 32) cohort. Four adverse events were recorded, two in each cohort, but these were not related to the rod material. At the final follow-up, both Ti and CoCr cohorts showed significant improvement in spinal correction, including the Cobb angle, thoracic kyphosis, and rib hump size. The correction rates were 68.4% and 67.1% for the Ti and CoCr cohorts, respectively. No parameters differed significantly between the cohorts at any time. Survey data showed improved but similar outcomes in both cohorts. Both treatments (Ti and CoCr) produced similar results and were efficient in engendering clinically significant spine corrections. Clinical trial registration no.: UMIN000008838 (UMIN Clinical Trials Registry).

Spinal-Shortening Process Positively Improves Associated Syringomyelia in Patients with Scoliosis After Single-Stage Spinal Correction

Single-stage spinal correction without previous neurosurgical intervention has been attempted in patients with scoliosis associated with syringomyelia (SM). However, evidence to demonstrate its potential influence on associated SM from direct spinal correction is still lacking. The aim of the present study was to explore the role of spinal shortening in the prognosis of SM-associated scoliosis after single-stage spinal correction without previous neurosurgical intervention. Patients with SM-associated scoliosis without previous neurological intervention, who had undergone posterior direct instrumental correction (PDIC) without osteotomy and posterior vertebral column resection (PVCR) at a single center, were selected for comparative analysis. The basic demographic and pre- and postoperative imaging data of the spinal deformity and SM at the final follow-up were compared separately for the 2 different spinal correction procedures. A total of 23 patients were included in the final analysis: 13 had undergone PDIC and 10 had undergone PVCR. The mean follow-up period was 6.2 years (range, 5-9 years). At the final follow-up, the mean corrective rate of scoliosis and kyphosis was 65.7% and 48.4%, respectively. Obvious SM reduction was achieved in 11 patients (47.8%), with an average reduction of 37.3%. No patient experienced neurologic deterioration or had required further neurosurgical intervention for SM during follow-up. The patients who had undergone PVCR had had much more severe scoliosis (98.8° vs. 60.5°; P= 0.000) and kyphosis (74.8° vs. 43.6°; P= 0.032). Moreover, 80.0% of the patients who had undergone PVCR had experienced obvious SM improvement compared with 23.1% of those who had undergone PDIC (P= 0.007). The reduction of spinal cord tension is an important factor influencing SM improvement. As the most powerful spinal-shortening osteotomy, PVCR can effectively correct severe spinal deformities and improve associated SM. Single-stage posterior spinal correction can be a potential choice for selected patients with scoliosis and untreated SM using strict inclusion criteria, which will not only achieve safe spinal correction but could also steadily improve and stabilize SM.

Planned two-stage surgery using lateral lumbar interbody fusion and posterior corrective fusion: a retrospective study of perioperative complications.

To determine the effect of planned two-stage surgery using lateral lumbar interbody fusion (LLIF) on the perioperative complication rate following corrective fusion surgery in patients with kyphoscoliosis. Consecutive patients with degenerative scoliosis who underwent corrective fusion were divided into a control group that underwent single-stage posterior-only surgery and a group that underwent planned two-staged surgery with LLIF and posterior corrective fusion. We collected the patient background and surgical data and assessed the perioperative complication rates. We also investigated spinopelvic parameters and patient-reported outcome measurements (PROMs). One hundred and thirty-eight patients of mean age 69.8 (range, 50-84) years who met the study inclusion criteria were included. The two-stage group (n = 75) underwent a staged anterior-posterior surgical procedure, and the control group (n = 63) underwent single-stage surgery. There was no significant between-group difference in the incidence of perioperative complications, except for deep wound infection (reoperation is necessary for surgical site infection). Revision surgery within 3months of the initial surgery was more common in the control group (n = 8, 12.7%) than in the two-stage group (n = 3, 4.0%). Spinopelvic parameters and PROMs were significantly better in the two-stage group at 2years postoperatively. The complication rate for planned two-stage surgery was similar to that of previous posterior-only single-stage surgery. However, early reoperation was less common, and the degree of spinal correction and clinical results were significantly better after two-stage surgery.

Automatic Vertebrae Localization and Spine Centerline Extraction in Radiographs of Patients with Adolescent Idiopathic Scoliosis.

Adolescent Idiopathic Scoliosis (AIS) is lifetime disorder indicated by the abnormal spinal curvature, and it is usually detected in children and adolescents. Traditional radiographic assessment of scoliosis is time-consuming and unreliable due to high variability in images and manual interpretation. Vertebrae localization and centerline extraction from a biplanar X-ray is essential for pathological diagnosis, treatment planning, and decision making. The aim of this paper is to develop a fully automated framework to provide correct evaluation of anatomical landmarks and to extract vertebral and intervertebral discs' centroids. By knowing coordinates of each centroid, developed framework will estimate 2D deformity curve (centerline) called Middle Spinal Alignment (MSA) in frontal plane. By analyzing the MSA lines and deformity segments, many deformity parameters can be calculated which include vertebral transpositions, Cobb angles, apex vertebra position, etc., for planning spinal correction strategies and monitoring.

Transient fixation of L4 vertebra preserves lumbar motion and function in Lenke Type 5C and 6C scoliosis

This study investigated the efficacy of a novel surgical method that relies on the transient fixation of L4 in Lenke Type 5C and 6C adolescent idiopathic scoliosis. Thirty-six transient surgically treated L4 fixation patients were retrospectively evaluated. The first surgery involved mechanical correction of scoliosis; the lowest instrumented vertebra (LIV) was L4. After an average of 1.3 years (range, 0.3–3.4), the second surgery to remove transient L4 pedicle screws was performed. Radiographic parameters and SRS-22 scores were measured. Cobb’s angle, coronal balance, LIV tilting angle, and LIV coronal disc angle clearly improved after the first surgery (p < 0.01). After the second surgery, the corrected Cobb angle (p = 0.446) and coronal balance were maintained (p = 0.271). Although L3/S1 lumbar lordosis decreased after the first surgery (p < 0.01), after removal of transient L4 pedicle screws, it recovered slightly (p = 0.03). Similarly, the preoperative L3/4 lateral disc mobility eventually recovered after transient L4 screw removal (p < 0.01). The function domain of the SRS-22 showed better scores after removal of transient L4 screws (p = 0.04). L4 transient fixation surgery is beneficial for Lenke Type 5C and 6C scolioses that do not fully satisfy LIV (L3) criteria. It preserves L3/4 disc motion, increases functional outcomes, and maintains spinal correction and coronal balance.

Effects of preoperative intravenous amantadine sulfate infusion on wake up test duration and postoperative opioid consumption in adolescents undergoing spine corrective surgery

BackgroundAmantadine sulfate is both a dopamine agonist and N-methyle-D-Aspartate (NMDA) antagonist which can augment the levels of dopamine in the striate body by triggering dopamine release and inhibiting dopamine reuptake. This study evaluated the effects of amantadine sulfate as a dopamine agonist on intraoperative wake up test duration and as a NMDA antagonist on cumulative opioid consumption 48 h after surgery. MethodsA randomized controlled double blind study, where 60 ASA class I and/or II patients of both sexes, planned for spine deformity corrective surgery were enrolled and divided into two groups (30 patients each): Group A received intravenous (IV) amantadine sulfate infusion (200 mg), and Group B received Ringer's lactate IV infusion. ResultsForty-eight hours after surgery, morphine consumption in group A was significantly lower than that in Group B (21.24 ± 1.1 vs. 30.41 ± 2.12 P < 0.001). Dynamic visual analog scale score was lower group A than that in group B (0.8 ± 0.71 vs. 2.7 ± 0.84 P < 0.001). Moreover, anesthetic consumption in group A was lower than that in group B; however, no statistical difference in wake-up test duration or recovery time from anesthesia was found between both groups. ConclusionsPreoperative administration of amantadine sulfate decreases postoperative morphine consumption and dynamic VAS score in patients undergoing corrective spine surgery. However, despite being a dopamine agonist, amantadine has no effect on wake- up test duration.

Anatomy of the Human Cervical Spine and Spinal Cord at 20–22 Weeks of Intrauterine Development

Early and timely diagnosis of the spinal column and spinal cord pathologies, their intrauterine and postnatal correction require detailed knowledge of the anatomy and topography of the cervical spine in the fetus. The complex interactions of the cervical spine with the corresponding parts of the spinal cord and adjacent structures require detailed study during the embryonic period of ontogenesis.The aim of the study was to investigate the morphometric and topographic anatomical fetal features of the cervical spine and adjacent structures at 20–22 weeks of the intrauterine development.Material and methods. This study was performed on the sectional material from human fetuses, 20–22 weeks of development (20 human fetuses of both sexes), obtained from the fetal collection of the Department of Human Anatomy, Orenburg State Medical University. A standard set of morphological methods were applied in the study – macromicroscopic preparation, Pirogov method of cuts in three mutually perpendicular planes, production of serial histotopograms with Van Gieson staining, photography, morphometry.Results. It was found that during the studied periods of prenatal ontogenesis, the length of the cervical spine averaged 17.5±1.5 mm. The transverse size of the vertebral body in fetuses of 20–22 weeks of development throughout the cervical spine is of greater importance than the anteroposterior. The transverse and anteroposterior dimensions of the vertebral foramen gradually decrease in the craniocaudal direction. It was also demonstrated that it is necessary to remove the dura mater in order to obtain reliable dimensional characteristics of the spinal cord.Conclusion. Thus, the data obtained on the anatomy and topography of the spinal column and the spinal cord at the 20th – 22nd weeks of the human ontogenesis can serve as the morphological basis of fetal surgery.

Retrospective Analysis on Intraoperative Neuromonitoring (IOM) of Potential Nerve Injury in Scoliosis Correction Surgery

Iatrogenic spinal injury resulting in paraplegia or paraparesis after surgical correction of scoliosis deformity is a rare complication but is very detrimental to the patient. Intraoperative Neuromonitoring (IOM) has become the gold standard to monitor surgical procedures which has potential risks to damage the spinal cord. This study aimed to retrospectively analyze the role of IOM in predicting the severity and extent of neurological injury during and after spinal correction surgery in adult idiopathic scoliosis cases related to surgical variables. This was a retrospective cohort study conducted at Dr. Cipto Mangunkusumo National Central Hospital, Fatmawati Central Hospital, and dr. Drajat Prawiranegara General Hospital during the period of 20 March 2018 to 20 August 2019. The primary outcomes were intraoperative monitoring status and post-operative neurological deficits status. Confounder data on scoliosis correction degree, intraoperative hemorrhage, and type of anesthesia used during surgery were retrieved. Chi-Square statistic was used in the analysis. Out of the ninety three patients eligible for this study, twenty two patients was detected as positive in IOM assessment. Four of the patients were found to be positive for post-operative neuromuscular defect. Thereby it can be concluded that IOM procedure can effectively prevent neurological deficits post-surgery with 81.8% specificity and 95.7% sensitivity among thosepositively detected by IOM. Some of the factors that could potentially influence false positive IOM results such as anesthetic used; dosage and administration procedures; magnitude of the scoliosis correction angle; and amount of bleeding during surgery have to be carefully analyzed.

Factors influencing upper-most instrumented vertebrae selection in adult spinal deformity patients: qualitative case-based survey of deformity surgeons.

The decision upper-most instrumented vertebrae (UIV) in a multi-level fusion procedure can dramatically influence outcomes of corrective spine surgery. We aimed to create an algorithm for selection of UIV based on surgeon selection/reasoning of sample cases. The clinical/imaging data for 11 adult spinal deformity (ASD) patients were presented to 14 spine deformity surgeons who selected the UIV and provided reasons for avoidance of adjacent levels. The UIV chosen was grouped into either upper thoracic (UT, T1-T6), lower thoracic (LT, T7-T12), lumbar or cervical. Disagreement between surgeons was defined as ≥3 not agreeing. We performed a descriptive analysis of responses and created an algorithm for choosing UIV then applied this to a large database of ASD patients. Surgeons agreed in 8/11 cases on regional choice of UIV. T10 was the most common UIV in the LT region (58%) and T3 was the most common UIV in the UT region (44%). The most common determinant of UIV in the UT region was proximal thoracic kyphosis and presence of coronal deformity. The most common determinant of UIV in the LT region was small proximal thoracic kyphosis. Within the ASD database (236 patients), when the algorithm called for UT fusion, patients fused to TL region were more likely to develop proximal junctional kyphosis (PJK) at 1 year post-operatively (76.9% vs. 38.9%, P=0.025). Our algorithm for selection of UIV emphasizes the role of proximal and regional thoracic kyphosis. Failure to follow this consensus for UT fusion was associated with twice the rate of PJK.

Optimization of pedicle screw position using finite element method and neural networks

The application of pedicle screws in instrumentation of the spine is widely used in spine correction surgeries. High stresses can be developed in the region surrounding the screw, and it is important to understand how to minimize this stress in order to reduce risk of patient harm. Traditional studies have used FEM (finite element method) to evaluate the best position and orientation of the pedicle screws; however, such approach demands iterative simulations to find the minimum stress position. This work has used an optimization-based method, based on neural network and genetic algorithm, to test different pedicular screw positions. By performing simulations of different screw positions through finite element analysis and using the results to train an artificial neural network, a less computationally intensive method of determining stress was found. The mathematical model created was optimized through a genetic algorithm and used to find a trajectory that results in lower mechanical stress between the pedicle screw and the vertebra. The results of the ANN approach show a reduction of 5.25% in the von Mises stress when compared to the FEA. Regarding the optimal trajectory, the angles differences were 2° in sagittal plane and 1.4° in transverse plane, hence showing good results.

Whole-genome methylation analysis reveals novel epigenetic perturbations of congenital scoliosis

Congenital scoliosis (CS) is a congenital disease caused by malformations of vertebrae. Recent studies demonstrated that DNA modification could contribute to the pathogenesis of disease. This study aims to identify epigenetic perturbations that may contribute to the pathogenesis of CS. Four CS patients with hemivertebra were enrolled and underwent spine correction operations. DNA was extracted from the hemivertebrae and spinal process collected from the specimen during the hemivertebra resection. Genome-wide DNA methylation profiling was examined at base-pair resolution using whole-genome bisulfite sequencing (WGBS). We identified 343 genes with hyper-differentially methylated regions (DMRs) and 222 genes with hypo-DMRs, respectively. These genes were enriched in the mitogen-activated protein kinase (MAPK) signaling pathway, calcium signaling pathway, and axon guidance in Kyoto Encyclopedia of Genes and Genomes (KEGG) pathways and were enriched in positive regulation of cell morphogenesis involved in differentiation, regulation of cell morphogenesis involved in differentiation, and regulation of neuron projection development in Biological Process of Gene Ontology (GO-BP) terms. Hyper-DMR-related genes, including IGHG1, IGHM, IGHG3, RNF213, and GSE1, and hypo DMR-related genes, including SORCS2, COL5A1, GRID1, RGS3, and ROBO2, may contribute to the pathogenesis of hemivertebra. The aberrant DNA methylation may be associated with the formation of hemivertebra and congenital scoliosis.

Image-Guided Tethering Spine Surgery With Outcome Prediction Using Spatio-Temporal Dynamic Networks.

Recent fusionless surgical techniques for corrective spine surgery such as Anterior Vertebral Body Growth Modulation (AVBGM) allow to treat mild to severe spinal deformations by tethering vertebral bodies together, helping to preserve lower back flexibility. Forecasting the outcome of AVBGM from skeletally immature patients remains elusive with several factors involved in corrective vertebral tethering, but could help orthopaedic surgeons plan and tailor AVBGM procedures prior to surgery. We introduce an intra-operative framework forecasting the outcomes during AVBGM surgery in scoliosis patients. The method is based on spatial-temporal corrective networks, which learns the similarity in segmental corrections between patients and integrates a long-term shifting mechanism designed to cope with timing differences in onset to surgery dates, between patients in the training set. The model captures dynamic geometric dependencies in scoliosis patients, ensuring long-term dependency with temporal dynamics in curve evolution and integrated features from inter-vertebral disks extracted from T2-w MRI. The loss function of the network introduces a regularization term based on learned group-average piecewise-geodesic path to ensure the generated corrective transformations are coherent with regards to the observed evolution of spine corrections at follow-up exams. The network was trained on 695 3D spine models and tested on 72 operative patients using a set of 3D spine reconstructions as inputs. The spatio-temporal network predicted outputs with errors of 1.8 ± 0.8mm in 3D anatomical landmarks, yielding geometries similar to ground-truth spine reconstructions obtained at one and two year follow-ups and with significant improvements to comparative deep learning and biomechanical models.

Revision Surgery Rates After Minimally Invasive Adult Spinal Deformity Surgery: Correlation with Roussouly Spine Type at 2-Year Follow-Up?

Spinopelvic parameters have hitherto dictated much of adult spinal deformity (ASD) correction. The Roussouly classification is used for the normal adult spine. We evaluated whether a correlation would be found between the Roussouly type and the rate of revision surgery in patients with ASD undergoing circumferential minimally invasive spinal (cMIS) correction. A multicenter retrospective review of patients who had undergone cMIS surgery for ASD was performed. The inclusion criteria were age ≥18 years and 1 of the following: coronal Cobb angle >20°, sagittal vertical axis >5 cm, pelvic tilt >20°, pelvic incidence (PI) to lumbar lordosis (LL) mismatch >10°, cMIS surgery, and a minimum of 2 years of follow-up data available. The patients were classified by Roussouly type, and the clinical and radiographic outcomes were evaluated. A total of 104 patients were included in the present analysis. Of the 104 patients, 41 had Roussouly type 1, 32 had type 2, 23 had type 3, and 8 had type 4. Preoperatively, the patients with type 4 had the highest PI (P=0.002) and LL (P < 0.001). Postoperatively, the PI-LL mismatch, Cobb angle, and sagittal vertical axis were not different among the 4 groups. However, the patients withtype 2 had had the highest rate of complications (type1, 29.3%; type 2, 61.3%; type 3, 34.8%; type 4, 25.0%;P=0.031). The reoperation rates were comparable (type 1, 19.5%; type 2, 38.7%; type 3, 13.0%; type 4, 12.5%;P=0.097). The reoperation rates for adjacent segment degeneration or proximal junctional kyphosis were also comparable (P= 0.204 and P= 0.060, respectively). We did not find a clear correlation between Roussouly type and the rate of revision surgery foradjacent segment disease or proximal junctional kyphosis in patients who had undergone cMIS surgery for ASD.

Unexpected Complications after Corrective Spinal Fusion Surgery for Adult Spinal Deformity with Severe Hip Contracture

Introduction: In cases with markedly decreased hip function, patients predominantly utilize spine movement while standing up to compensate for the hip malfunction. However, spinal fusion surgeries might lead to the disruption of this compensatory mechanism, resulting in difficulties in walking and standing up as well as proximal junctional failure (PJF) due to the excessive stress on the spine caused by the pendulum-like motion needed for standing up. Hence, in patients with severe hip pathology, surgeons should be cautious about the indication for spinal fusion, which inevitably affects spinal mobility. This is the first report presenting a case that supports the aforementioned theory. Case Report: In this study, we report the case of a 76-year-old Japanese woman who underwent corrective spinal fusion surgery for spinal scoliosis secondary to hip contracture. The patient exhibited post-operative complications, such as unexpected difficulty in walking and standing up and PJF. The patient underwent a revision spinal surgery with an extension of spinal fusion for PJF and muscle release around the hip for hip contracture which resulted in improved walking and standing movements with no reports of pain. Conclusion: Spinal fusion surgeries performed on patients with severe hip pathology could cause early PJFs and unexpected decline in activities of daily living. Patients with such risks often do not complain of hip symptoms before spinal correction surgery. Surgeons should routinely evaluate hip joints and be cautious about the indication for spinal fusion which inevitably affects spinal mobility. Keywords: Hip joint contracture, spinal correction surgery, proximal junctional failure, muscle release around the hip.

Implications of amantadine sulfate usage on intraoperative hemodynamics in patients undergoing corrective surgeries for spine deformities: a randomized-controlled trial

Background Corrective spine s urg eries for scoliosis and/or kyphosis are a major challenge. This study was carried out to test whether preoperative intravenous administration of amantadine sulfate could affect the intraoperative hemodynamics in patients undergoing major spine corrective surgeries. Patients and methods This is a prospective, randomized double-blind clinical trial. Twenty adult patients were included in the study. Patients were randomized equally into two groups (10 patients each). Group A received an intravenous amantadine sulfate infusion of 200 mg in a 500 ml bottle. Group B (control group) received a ringer lactate intravenous infusion (placebo). Unlabeled bottles were given slowly 3 h before the surgery. Intraoperative hemodynamics systolic, diastolic, mean arterial blood pressure, and heart rate were recorded. Results The intraoperative mean arterial blood pressure was significantly lower in group A than group B at induction) 57.5 ± 7.94 vs. 64.9 ± 6.18, P = 0.002) and half an hour after induction) 51.8 ± 6.66 vs. 59.2 ± 6.37, P = 0.001). Also, the intraoperative mean heart rate was significantly lower in group A than group B at induction (88.5 ± 16.07 vs. 101.2 ± 19.89, P = 0.032), 3 h after induction (81.5 ± 10.33 vs. 90.8 ± 16.46, P = 0.039), and at the end of the operation (95.3 ± 7.93 vs. 103.6 ± 9.37, P = 0.004). Conclusion Preoperative administration of intravenous amantadine sulfate in corrective spine surgery has minimal effect on intraoperative hemodynamics in terms of the mean arterial blood pressure and heart rate.

Finite Element Analysis of an Improved Correction System for Spinal Deformity.

Surgical treatment for spinal deformity aims to correct malformation, release the nerves, and reconstruct spinal stability. To explore and develop a new improved spinal correction system (ISCS) for clinical application, we studied the stability and biomechanical characteristics of the ISCS through finite element analysis and comparison of the ISCS with the pedicle screw and rod system (PSRS). Using L1-L3 CT image data of a normal adult male lumbar spine for establishment of L1-L3 finite element model, we established posterior internal fixation models for a comparative finite element analysis of PSRS and ISCS. An axial load of 500 N and a moment of 10 N•m were applied to L1 to simulate flexion, extension, lateral bending, and axial rotation. Stress distribution characteristics, load sharing, strain bending stiffness and strain angle change of the models were measured. In flection and extension directions, the maximum stress of the L2 vertebral body and the L1/2 and L2/3 discs in PSRS was less than that of ISCS. In lateral bending and axial rotation directions, the maximum stress between PSRS and ISCS was similar. However, the stress shielding rate of L2, L1/2, and L2/3 intervertebral discs in ISCS was significantly lower than that of PSRS. We also found that both models had similar angular displacement and maximum displacement in lateral bending direction, but PSRS had a lower angular displacement and maximum displacement in flection and extension directions. Finally, we showed that PSRS had similar angular displacement and a lower maximum displacement compared with ISCS in axial rotation, whereas ISCS had lower bending stiffness than PSRS in different directions. ISCS can effectively fix spinal deformities compared to PSRS. ISCS provides a new option for orthopedic surgery treatment of scoliosis and, therefore, warrants further clinical studies in patients with other spinal deformities.

Intraoperative neurophysiological monitoring during spinal correction surgery in patients with congenital scoliosis: Its feasibility and influencing factors

Intraoperative neurophysiological monitoring during spinal correction surgery in patients with congenital scoliosis: Its feasibility and influencing factors